Aragorn looked on the slain, and he said: 'Here lie many that are not folk of Mordor. Some are from the North, from the Misty Mountains, if I know anything of Orcs.... And here are others strange to me.'....

There were four goblin-soldiers of greater stature, swart, slant-eyed, with thick legs and large hands. They were armed with short broad-bladed swords, not with the curved scimitars usual with Orcs: and they had bows of yew, in length and shape like the bows of Men. Upon their shields they bore a strange device: a small white hand in the centre of a black field; on the front of their iron helms was set an S-rune, wrought of some white metal....

Then [after his failed bid to imprisonGandalf] Saruman... perceived the peril of standing between enemies, a known traitor to both. His dread was great, for his hope of deceiving Sauron, or at the least of receiving his favour in victory, was utterly lost. Now either he himself must gain the Ring or come to ruin and torment.

Unfinished Tales, Part 3, Ch 4, The Hunt for the Ring: Of the Journey of the Black Riders

[Aragorn said,] 'Regiments of black crows... have passed over Hollin. They are not natives here; they are crebain out of Fangorn and Dunland.... I think they are spying out the land.'

The Fellowship of the Ring, LoTR Book 2, Ch 3, The Ring Goes South

'There is evil afoot in Isengard.... It is as Gandalf feared: by some means the traitor Saruman has had news of our journey. It is likely too that he knows of Gandalf's fall. Pursuers from Moria may have escaped the vigilance of Lórien, or they may have avoided that land and come to Isengard by other paths. Orcs travel fast. But Saruman has many ways of learning news. Do you remember the birds?'

[Said Aragorn,] '... we came... down the leagues of the Great River to the falls of Rauros. There Boromir was slain by the same Orcs whom you destroyed.'

The Two Towers, LoTR Book 3, Ch 2, The Riders of Rohan

[Said Pippin] 'It seems a year since we were caught. ... I reckon that three very horrible days followed.... I am not going into details: the whips and the filth and stench and all that; it does not bear remembering.' With that he plunged into an account of Boromir's last fight and the orc-march from Emyn Muil to the Forest.

'[Our enemies] have filled themselves with new doubts that disturb their plans. No tidings of the battle will come to Mordor, thanks to the horsemen of Rohan; but the Dark Lord knows that two hobbits were taken in the Emyn Muil and borne away towards Isengard against the will of his own servants. He now has Isengard to fear as well as Minas Tirith. If Minas Tirith falls, it will go ill with Saruman.'

The Two Towers, LoTR Book 3, Ch 5, The White Rider

'All this about the Orcs of Barad-dûr, Lugbúrz as they call it, makes me uneasy,' said Aragorn. 'The Dark Lord already knew too much and his servants also; and Grishnákh evidently sent some message across the River after the quarrel. The Red Eye will be looking towards Isengard. But Saruman at any rate is in a cleft stick of his own cutting.'

'Yes, whichever side wins, his outlook is poor,' said Merry. 'Things began to go all wrong for him from the moment his Orcs set foot in Rohan.'

The Two Towers, LoTR Book 3, Ch 9, Flotsam and Jetsam

'... Saruman certainly looked in the Stone since the orc-raid, and more of his secret thought, I do not doubt, has been read than he intended. A messenger has been sent to find out what he is doing.'

The Two Towers, LoTR Book 3, Ch 11, The Palantír

It needed the demonstration on Dol Baran of the effects of the Orthanc-stone on Peregrin to reveal suddenly that the "link" between Isengard and Barad-dûr (seen to exist after it was discovered that forces of Isengard had been joined with others directed by Sauron in the attack on the Fellowship at Parth Galen) was in fact the Orthanc-stone — and one other palantír [from Minas Ithil].